The present invention relates to a method of manufacturing a ceramic film, a method of manufacturing a ferroelectric capacitor, a ceramic film, a ferroelectric capacitor, and a semiconductor device.
As a ferroelectric film applied to semiconductor devices (ferroelectric memory (FeRAM), for example), a ferroelectric film having a perovskite structure (PbZrTiO, for example) and a ferroelectric film having a layered perovskite structure (BiLaTiO, BiTiO, or SrBiTaO, for example) have been proposed.
Pb or Bi contained in the material for the ferroelectric film easily volatilizes at low temperature due to high vapor pressure. Since a high-temperature heat treatment is performed during the crystallization process of the ferroelectric film, Pb or Bi bonds to oxygen in the atmosphere necessary for crystallization of the ferroelectric and scatters, thereby adversely affecting the characteristics of the crystallized ferroelectric film.
Since the lattice constant of the crystallized ferroelectric film does not necessarily coincide with the lattice constant of the metal film used as the electrode material, strain due to lattice mismatch occurs in the case where the ferroelectric film is applied to a ferroelectric capacitor having a metal-insulator-metal (MIM) structure, whereby the characteristics tend to deteriorate. In order to eliminate such a lattice mismatch, a capacitor structure in which an alloy film is formed between the ferroelectric film and the electrode has been proposed (see pamphlet of international publication No. 00/17929).